Horton

Re: speeding up planning with partitions

Jesper Pedersen <jesper.pedersen@redhat.com>

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From: Jesper Pedersen <jesper.pedersen@redhat.com>
To: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
Cc: "Imai, Yoshikazu" <imai.yoshikazu@jp.fujitsu.com>, 'Amit Langote' <amitlangote09@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, David Rowley <david.rowley@2ndquadrant.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Justin Pryzby <pryzby@telsasoft.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2019-03-05T15:57:57Z
Lists: pgsql-hackers 
On 3/5/19 5:24 AM, Amit Langote wrote:
> Attached an updated version.  This incorporates fixes for both Jesper's
> and Imai-san's review.  I haven't been able to pin down the bug (or
> whatever) that makes throughput go down as the partition count increases,
> when tested with a --enable-cassert build.
> 

Thanks !

I'm seeing the throughput going down as well, but are you sure it isn't 
just the extra calls of MemoryContextCheck you are seeing ? A flamegraph 
diff highlights that area -- sent offline.

A non cassert build shows the same profile for 64 and 1024 partitions.

Best regards,
  Jesper

Commits

  1. Clean up handling of constraint_exclusion and enable_partition_pruning.

  2. Add test case exercising formerly-unreached code in inheritance_planner.

  3. Speed up planning when partitions can be pruned at plan time.

  4. Avoid crash in partitionwise join planning under GEQO.

  5. Avoid passing query tlist around separately from root->processed_tlist.

  6. Build "other rels" of appendrel baserels in a separate step.

  7. Get rid of duplicate child RTE for a partitioned table.

  8. Rearrange make_partitionedrel_pruneinfo to avoid work when we can't prune.

  9. Don't copy PartitionBoundInfo in set_relation_partition_info.

  10. Move building of child base quals out into a new function

  11. Reorganize planner code moved in b60c39759908

  12. Move inheritance expansion code into its own file

  13. Fix inherited UPDATE/DELETE with UNION ALL subqueries.

  14. Rearrange planner to save the whole PlannerInfo (subroot) for a subquery.